The present invention relates to a method of inserting an artificial intraocular lens into an eye, and more particularly to a method of deforming such lens and inserting it in deformed state into the eye through a corneal incision of minimal size.
In eye surgery for treatment of conditions such as natural eye lens cataracts, a common procedure is to remove the cataracted lens through an incision in the wall of the cornea of the eyeball, and replace it by an artificial intraocular lens. Intraocular lenses are usually made flexible, foldable, etc., to permit size reduction thereof for facilitating their insertion through the cornea, with the highly advantageous result that an incision of absolute minimum size will suffice.
Even though their lens bodies or optics may be curlable, foldable or otherwise deformable to reduce their overall girth, such intraocular lenses, for example silicone lenses, often have haptics extending from the periphery of their optics, i.e. normally expanded resilient appendages connected to the central lens body or optic, to aid lens seating in the eye. Preferably, these flexible lenses must somehow be maintained in curled, folded or similar reduced girth condition, with their haptics in contracted state, during insertion into the eye in order to fit without difficulty through a minimum size incision.
U.S. Pat. No. 4,573,998 to Mazzocco (Mazzocco '998), and U.S. Pat. No. 4,534,069 to Kelman (Kelman '069), are among typical proposals which have been made to provide the intraocular lens in temporarily reduced girth condition for incision insertion purposes.
Mazzocco '998 contemplates curling the silicone or the like optic, together with the haptics, in the form of a lens compact in a sleeve type instrument, inserting the sleeve end physically through the eye incision, and forcing the compacted lens, with the aid of a plunger or the like, out of the sleeve end while the end projects into the eye through the incision. However, this approach requires that the incision must be large enough to permit insertion therethrough of not only the lens, but also the sleeve end.
It would, of course, be highly advantageous if only the compacted lens and not also a sleeve instrument needed to be inserted into the eye, since the incision could then be made of substantially reduced size, considering that the sleeve wall thickness adds to the lens girth at both diametric sides.
Kelman '069 provides one solution to this problem, by temporarily molding the lens, with the haptics in contracted state overlapping the central optic, in a layer of adhesive acting material which is non-toxic and otherwise compatible with as well as soluble in the eye fluid, and which connects the haptics in that contracted state to the optic during lens insertion into the eye through the incision, yet such solution does not involve physically grossly deforming the overall lens mass to reduce its girth.